Cameroon Mountain is an isolated volcanic mass, covering 800 square miles and towering higher than any other mountain in Western Africa. It is also the nearest African mountain to any sea coast, as it rises from the waters of the Gulf of Guinea, a spectacular site when viewed from sea. The offshore island of Malabo, the capital of Equatorial Guinea, is south of the mountain. On this island, another volcano, Pico de Santa Isabel, rises to 9,868 ft. (3,008 m.). The mountain's high summit crater is known as Great Camerron, Fako, or locally as Mongo-ma-Lobo, the Mountain of Thunder. A second distinct summit is the densely forested Little Cameroon (5,820 ft.). The entire massif is known locally as Mongo-mo-Ndemi, or Mountain of Greatness.

Cameroon is home to some of the heaviest rains on earth, receiving hundreds of annual inches on the seaward side of the mountain. The highest reported precipitation was in the town of Debundja, which received 577 inches in 1919. The majority of Cameroon's rain falls in July, August, and September. The mountain has had a history of violent eruptions, including seven in the Twentieth Century. It erupted on March 28, 1999, for the first time since 1982.

Locals of the Bakweiri ethnic group attribute the recent eruption to the death of Monono Otto, a traditional chief.